The observed small orbital radii of massive extrasolar planets around the central solar-type stars can be explained by the mechanisms of orbital migration. The scenario is: the planet forms in the protoplanetary disk and induces planet–disk tidal interactions resulting in the inward migration of the planet. In this thesis, we first construct a onedimensional disk model corresponding to the observational constraints and then investigate the effects caused by the embedded planet, including the regulations of the disk surface density and the planetary orbital radius. Using numerical simulations, the evolution of the disk as well as the changes in the planetary orbital radius are produced. The massive planet (∼ 1MJ ) opens a gap quickly in the vicinity of its location, and the gap would move with the migrating planet. If the planet forms earlier in the disk, its extent of migration is larger. We also find that the more massive planet migrates faster initially, but the resulting change in orbital radius is not obvious (it would stop migrating earlier).
